<p>The number of remote accesses and the number of distinct remote sites accessed byglobal transactions in a distributed database environment are characterized. Bothmeasures are important in determining the overhead of distributed transaction processingand are affected by the distribution of transaction size (number of distinct objectsaccessed by a transaction) and the distribution of remote accesses made by atransaction. Keeping the mean transaction size fixed, it is shown that in the case of somecommonly used distributions for the number of remote accesses variable size transactionsaccess fewer distinct remote sites on the average than fixed size transactions. Also, forthese and some other distributions the mean number of remote accesses is independentof the distribution of transaction size, but this is not generally true.</p>